DARPA and Boston Dynamics have unveiled their most advanced humanoid robot yet: Atlas. At 6’2″ and 330lbs, Atlas is incredibly imposing; with 28 hydraulically actuated joints, LIDAR and stereo vision, a beefy on-board computer, and some of the most advanced robotic limbs ever conceived, Atlas is remarkably human-like in its behavior. While Atlas is initially conceived as a disaster response robot, such as cleaning up and looking for survivors at after a Fukushima-like disaster, it’s easy to imagine Atlas being the basis of a robotic army, supported by BigDog mules.

Today a rather cryptic release from 5D Robotics hinted at a growing trend in military research: rather than finding new and innovative ways to strap weight to our human soldiers, how about we just bring along a robot pack mule or two?

Boston Dynamics, the robotics company behind AlphaDog, Petman, and Cheetah, has now outfitted its BigDog robot with an arm that’s capable of flinging 50-pound (23kg) concrete blocks across a room at high speed. This really is as terrifying as it sounds — but if you don’t trust me, watch the video below.